Brake-testing device for automobiles



c. F. COWDREY BRAKE TESTING DEVICE FOR AUTOMOBILES Jan. 5,192 7 1,568,803

Filed June 21, 19.24 2 Sheets-Sheet 1 A TTOFP/ E y' Jan. 5,1926. 1,568,803

C. F. COWDREY BRAKE TESTING DEVICE] FOR AUTOMOBILES Filed June 21, 1 Z Sheets-Sheet 2 ATTORNEY f v ,/||||I|||.

inanim te. -'1 ,s6s,so3 IUNITED STATES PATENT. OFFICE."

' cnmns r; cowDnnY, orrncntnune, mssacnusn'r'rs.

BRAKE-TESTING DEVICE non nuromonrnns.

Application fiJed June 21, less. Serial no. 721,421.

To all whom it may concem: I other words, the true action of abrake upon' ,Be it known the I, CHARLES-F. G perm, a continuously rotating wheel cannot be dea citizen of the United StatesjrSiding in termined by merely indicating the force re- Fitchburg, county of Worcester, and'fitate quired to turn a wheel fnbm a standing 60 of Massachusetts, have invented an Iniproveposition thru a small angle.

ment in Brake-Testing Devices for Auto Having the above matters in mind the mobiles, of which the following description, present invention relates to a brake testing in connection with the accompanying draw device that will correctly indicate'the action ings, is a specification, like characters on the of they brake upon a wheel under running 104 drawings representing like parts: conditions. In 'carryin out the present in- This invention relates to means tor testing vention a head-is provided that is adapted the action of the brakes upon the wheels of to be engaged with an automobile wheel to an automobile or othervehicle. turn it thru successive-- revolutions under It is very important that the brakes of brake resistance and the head is'provided- 70 an automobile be at all timesproperly adwith means forlihdicatingthe turning force justed so that the'brake bands upon the, imparted to the wheel by the head. opposite wheels'will-act with equal or sub-- After the action of a brake,band upon stantially'. equal orce,;because the speed of one wheel has been tested and thg reading an automobile cannot be checked promptly of the indicator noted, the brake testing de- 75 unless each brake band acts with a-substanvice is applied to the opposite wheel bf the tial.retarding forcempon its wheel, and if automobile and the action of the brake hand one brake band exerts a greater retarding upon this wheel is tested while the brake i force than the brake'bandof the opposite applied the same as during the testing' o wheel, the automobile itself-,gis likely to the first wheel; and if a difi'erent reading is! 89 swerve from its f t-path'of traveliwith obtained in testing. the second wheel the dangerous result. brake bands obviously need adjustment.

7 Many of the automobile accidents that now One feature of the present-invention I.

frequently occur are due 'to faulty brakes resides in a head consisting of relatively rothat fail to check 'thespeed of the autotatableparts having yielding means for-immobile promptly, or cause. the automobile to parting the rotative movement, from one swerve from its direct path. The improper part to the other, and in an indicator for adjustment of automobile brakes isdue, to Q indicating the relative movement of the a large degree, to the lack of practical means parts while rotating a wheel. for testing the action of the brakes upon Another feature of the present invention 90 the wheels of an automobile. 'When brakes resides in arms upon said head which may are provided upon all four wheels of an be adjusted to extend from one face of automobile, the importance of maintainin the head to engage and rotate the wheel upthe brakes properly adjusted becomes of sti on one side of an automobile, and adjusted greater-importance, for if the brakes upon to extend from the opposite face of-the 5 i 40 the opposite front wheel operate with u'n-- head when thelatter is applied to the opequal retarding effect and the brakes upon posite wheel of the automobile.

the opposite rear wheel also act with on: Another feature of the invention resides equal force, thejtendency of the automobile in indicator means. for indicating upon each to swerve from a direct path upon applicaface of the head the turning force applied tion of the brakes may lie-increased. to a wheel.

' Heretofore it has been proposed. to em,- Other features of the invention and novel ploy. a lever or other operating qneans to combination of parts in addition to the above turn an automobile wheel thru a small angle will be hereinafter described in connection while the brake is applied, and to indicate with the accompanying drawings which Q the turning force applied to the wheel. illustrate one good practical form thereof.

This proposed construction serves to indi- I In the drawings- H cate' the force required to impart initial Fig. 1 is a perspective view of a brake Q tativefmovem'entto a wheel to turn it from testing device constructed in accordance I "a standing position; but does not indicate with the present invention and shown in the true action of the brake band uponthe position to test the-brake of an automobile wheel under actualrupning condition. In whee].-

Fig. 2 is an enlarged vertical sectional view thru the gear casing of Fig. 1.

Fig. 3 is an enlarged front view of part of the mechanism shown in Fig. '1, the gear cover plate being removed.

Fig. 4 is a face view of the head of the present invention-shownapplied to a wheel. parts of the head being shown in section; and

Fig. 5 is a sectional view taken on the line 5 of Fig. 4.

In the embodiment of the invention illustrated, the brake testing ,device is shown as mounted upon a truck 10 provided with wheels or rollers lland the'truck may be readily moved from one place to another by means of the .handle 12. Upon the truck 10 is mounted a supportingframe consist ing of the spaced upstanding columns 13 which are rigldly secured to the upper face of the truck 10 and the cohunnsare con nected at their upper ends-by the bridge member 14. Between the spaced columns 13 is slidably mounted the gear casing 15. in which casing is rotatably mounted the main driving shaft 16 having an outwardly extending squared portion 17 adapted to engage and rotate the wheel operating head 18.

In the construction shown power means is provided for rotating the head 18 and to this end the main shaft 16 is driven thru a series of gears by an electric motor 19 which is conveniently secured to the lower face of the gear casing 15. The driving shaft of the electric motor 19'is provided with a bevel gear 20 which meshes with a bevel gear 21 secured to the worm shaft 22 mounted in a housing. A worm 23 upon the shaft 22 meshes with and drives the worm gear 24 rotatably mounted upon the shaft 25, and enclosed in a gear chamber provided with a cover plate 26. The worm gear 2 1 drives a pinion 27 mounted upon the shaft 25. It is desirable to reverse the direction of rotation of the main shaft. 16 in testing wheels upon the opposite sides of an automobile, and in the present case reversing gears 28, and 29 are provided between the pinion 27 and the gear 30 supported by the shaft 30. The gear 30 meshes with and drives the gear 31 keyed to the main shaft 16. The reversing mechanism shown is of well known construction and the gears 28 and 29' are positioned so that the gear 28 meshes with and is driven by the pinion 27 and the gear 29 is driven by the gear 28. These two gears are mounted upon the lever 32, rockingly supported by the shaft 25, the forward end of which lever extends thru the gear casing to form the handle 33. When the handle is rocked downwardly the gear 29 is moved into. driving engagement with the gear 30 to rotate the shaft 16 in one direction, andwhen the-lever 32 is rocked upwardly the gear 28 is engaged with the gear 30 and the shaft 16 is rotated in the opposite direction. The lever 32 may be secured in either of the positions just mentioned, or in an intermediate position,

by a pin adapted to enter in one of the holes with the gear 30.

The head 18, in the construction shown, consists of a hub portion 36 provided with an integral flange or disk portion 37, and rotatably mounted upon the hub 36 is a spider or wheel driving portion 38. The portions 37 and 38 are spaced apart, as shown in Fig. 5, to form a hollow chamber between them, in which gears and other partst'o be described may be enclosed. The hub 36 of the head 18 is provided with a central'opening 39 which is squared in cross section to conform to the squared end of the main shaft 16, the arrangement being such that the end 17 of this shaft may be inserted in the hub to support and rotate the same. An antifriction bearing 39 is preferably provided between the hub portion 36 and the spider or wheel engaging portion 38 of the driving head, to reduce friction between these parts, when one rotates about the other. This antifriction bearing may be constructed as usual, andconsists of an inner ring and an outer ring having a ball runway formed between them. The inner ring is mounted upon the hub 36 and is clamped in place thereupon by tightening up the 1111b 40 and the outer ring fits snugly within an annular flange 41 integral with theportion 38 of the head 18. The nut 40 is shown as provided with an annular groove 'n which a piece of felt 42 may be mounted to prevent dirtfrom entering the space between the nut and the adjacent surroundin wall.

In the construction shown. means is provided for clamping the head 18 toa wheel of an automobile, so that vhen the head is rotated by the main shaft 16 it will turn the wheel under brake resistance. Various means might be provided for imparting movement f1 om the head 18 to the automobile wheeL-and in the construction shown this is accon'iplished by providing the portion 38 of the head'wit h ,three legs 43 which extend outwardly from the head portion 38 ina radial direction. The legs 43 are hollow and are shown as squared in cross section and within each leg is slidably mounted an elongated block 44, the outer end of which is provlded with a stub shaft 45. Upon each stub shaft 45 is mounted a laterally extending tire-engaging arm 46 and the arms 46 are rotatably securedto the shafts 45 so a and to this end theouter end portion ofeach-stub shaft 45 is provided with a trans-- end of-the sliding block. 44. As aresu'ltof shown in full lines in Fig. 5 to the-position shown in dotted lines. It is desirable to provide means for maintaining thearms 46- in either of the positions. shown in Fig. 5,

versely extending pin 47 which pinis adapted to enter a no'tch formed across'the hub of the arm .46 and the arm 46 is normally held in engagement with the pin 47 by a coiled spring 48 confined'betweenthe inner face of the hub'of the arm 46 and the outer this construction'the aria 46 may readily be rotated from the full line position in Fig. 5'

to the dotted line position. upon forcing it inward sufficiently to disengage the notch formed in theouter face of this lever from the pin 47 l It is desirable to provide means for may ing the arms 46 inwardly simultaneously into clamping engagement with the tread'of the automobile wheel 50 that the head 18 will be properlycentere'd'upon the wheel.

as the clamping arms 46 grip the wheel.- To this end, 1n the construction shown, each sliding block '44 is threaded at its inner end to receive a threaded shaft 49 rotatably mountedlwithin a leg 43. The inner end of each threaded shaft 49 is provided with) a gear 50 which meshes with ,a driving-gear 51. Twoof. the driving gears 51 aresecured to the opposite ends of the shaft 52 rotatably mounted within the chamber formed between the portions 37 and38 of the head 18'. The shaft 52, may be manually rotated by means of a crank handle 53 which is removably secured to the stub shaft 54, the

inner end of which shaft-'is rovidedwith fa bevel gear 55 that meshes with a bevel ear 56 secured to the shaft52. A second s aft- ;57 mounted within the head 18 is driven As stated, the spider or wheel engaging from the shaft 52 by the cooperating bevel gears 58 and the third gear 51 is secured to and driven by the shaft 57. From the'consimultaneously rotated in one direction or.

the other by turning the crank handle 53.

ff' portion 38 of the head is rotatably mounted upon the hub 36 andthe hub 36 is mounted upon and driven "by-the main shaft 16. It

is desirable to provide means'for yieldingly.-- imparting rotative movement from the hub portion36 to the spider portion 38 and to :this end, in thecgnstruction shown, a coiled spring 58"is provided, one Iend'of which spring is securedto a transversely extending pin 59 rigidly secured'to thespider portion 5 .38, and. the-other= end of this spring is secured to a transversely extending pin 60,

' rigidly secured to the flange 1' ,po

7 l V rtion 37, of the hub 36,- As a result of-theconstruction the indicator upon either face ofthe head18.

---moved from thejsha'ft l6 after cone-wheel has been tested and then turnedand. inserted iwardsfthe supporting-frame 13. v This-necessitates shift; arms 46 from ti! of: whee-(n18 is exposed. V

posite wheels of an automhbile, 'the depres.

described, whenthe'hr-ake testing device is applied to a wheel of an automoblle, and

placed upon the'spring 58 to turn the autoanobile wheel under brake resistance. It is essential that the forceexerted to turn the wheelbe indicated, and to this end,in the present construction, the pin 59 is provided with a pointer 61 that extends thru an arouate slot 62 in the hubflange 37., and the pin 60 is-provided with 'a' pointer 63 which ex. v tends thru an arcuate slot 64 in the spider portion 38, Graduations are provided ad: jacent'the arcuate' slots 62 and 64, so that v the extent .to which the hub portion 36 ro-.. fates within the spider portion 38. may be readily noted by observing the position-of When the brake-testing device oft-he present invention is applied to a wheel upon one side of an automobile, the main driving shaft 16 is driven in one direction, andwhen the brake testing device is applied to a wheel upon-the opposite side of the automobile it is necessary to rotate this shaft in the opposite directionin order to rotate each automobilewheel in a forward direction. From the construction'of thehead-flS described it will be seen that thehub portion '36 must always be rotated by the main driving shaft in a direction to place the-spring 58 under tension butwhen the direction ftheshaft 16 is .reversed'the rotative move ent of this shaft is then in a .directionj't spring 58 rather than tension i To overcome this difii 'uu l'ui rails is constructed so that it may be readily re- 6 upon the-shaft 16 with its opposite faceto- 0 a sition shown'in full lines -in--Fig. 5 to the position shown in dotted 1 lines in this figure. Upoh'iobs'erving. Figg -l I,"

of-the drawingit will be seen that then-hub. jj' flange 37 faces outwardly from theaautomo the wheel engaging bile wheel and-upon observingg i l jigs. 4and 5 y 'it will be seen that the head18 @ha .turned'around so thagthe spider port faces oiitwardly fronytheyautomobile w *ti; Since an indicator and cooperating, scale is provided upon each face H reading during thetesting f 'awheel may be/ ily noted,'irres pective 0t whiph fags In?tes tingthe brake action upon-the ops sion ,of the fodt fbrake pedalflshould be maintained the same thruoutjthe entire opera tion, and after the force required td-turn one'wheel under brake iesistancehas been determined by' the present. device the brake,

offithe headt leans- L tester is moved to the opposite wheel to determine. the force required to turn this wheel under brake resistance, and if the.

. ing the crank handle 53-to the horizontally extending shaft 66 rotatably mounted upon one of the uprights 13, and the inner end of this shaft is'provided with a bevel gear which meshes with and drives a bevel gear secured to the upper end of the threaded shaft 67, which shaft extends thru a threaded hole in a lug 68 formed upon one wall of the casing 15. i What is claimed is v 1. A brake tester for testing the action Of a brake upon a wheel of an automobile,

comprising incombination, a head engage-' ablewith a wheel of an automobile to rotate. the wheel under .brake resistance and consisting of: a hub portion and a wheel engaging portion rotatable upon the hub portion, means for rotating the hub-portion and operable to turn an automobile wheel when the brake is applied hard,-a spring for yieldingly imparting the rotative movement of-the hub portion to the wheel engaging portion, and an indicator actuated by the movement of one of said portions relative to the other to indicate the rotative force applied to the wheel.

2. A brake tester for testing the action of a brake upon a wheelo'f an automobile, comprishigin combination, a head engageable with a wheel of an automobile to rotate aboutthe wheel axis and constructed to turn the wheel under pronounced brake resistance, driving means for rotating said headto turn the wheel, a support for the driving-means which does not rotate with the' wheel, means upon the head adapted to yieldin response to the turning force exerted upon the wheel, and means operable by the yielding movement for indicating the force exerted to turn the wheel.

3. A brake tester for testing the actio of a brake upon'a wheel of an automobile, comprising in combination, a head engageable with a wheel of an automobile to rotatef with the wheel thru successive revolutfons to turn the wheel under brake resistance, means for'rotating said head to turn the yvheel under strong brake resistance, a sup "ort for the rotating means and relative y to which thewheel rotates, and an of a brake upon a wheel of an automobile,

comprising in combination, a head engageable with a wheel of an automobile to 1'0- tate with the wheel through successive revolutions to turn the wheel under brake resistance, power actuated means for rotating said head to turn the wheel, and an indicator upon the head for indicating the rotative force applied to the wheel.

5. A brake tester for testing the action of a brake upon a wheel of an automobile, comprising in combination, a supporting frame having a shaft, a head upon said shaft and engageable with a wheel of an automobile to rotate the wheel under brake resistance, means for rotating said head, and an indicator upon the head for indicating the rotative force applied to the wheel.

a 6. A brake tester for testing the action of a brake upon a wheel of an automobile, comprising in combination, a head adapted to be engaged with a wheel of an automobile to rotate the wheel continuously thru successive revolutions under brake resistance, means to rotate the head to turn the wheel, a support 'for the rotating means and relatively to which the wheel rotates thru successive revolutions, and indicating means upon the head for indicating the turning force applied to the wheel.

7. A brake tester for testing the action of a brake upon a wheel of an automobile, comprising in combination, a head having laterally extending arms adjustable into gripping engagement with the tread of an automobile wheel to turn the wheel thru successive revolutions, means for forcing the arms into gripping engagement with the tread, means for rotating the head to turn the wheel under brake resistance, and means upon the head for indicating the rotative force applied to the wheel.

8. A brake tester for testing the action of a brake upon a wheelof an automobile, comprising in combination, a head for rotating a wheel of an automobileunder brake resistance and consisting of a hub portion and a wheel engaging portion rotatable upon the hub portion and having projecting wheel engaging parts, means for rotating said hub portion, yielding means'i'or imparating rotative force from the hub portion to the wheel engaging portion, and means for indicating the force applied to the wheel.

9. A brake tester for testing the action of a brake upon a wheel of an automobile, comprising in combination, a head for rotating a wheel of an automobile under brake resist ance and consisting of a hub portion and a wheel engaging portion rotatable upon the hub portion, means for rotating said hub portion, yielding means for imparting rotaill) ' tiveforce from the hub portion to. the wheel engaging portion and constructed to turn thewheel under strontgxbrake resistance, and

means positioned by -e rotation of one of said portions relative to the other to indicate the force'applied to the wheel.

10. brake tester for testing the action of a brake upon a'wheel of an automobile, com-. prisingin combination, a head having laterally extending arms .enga cable with the tread of an automobile w eel, means for moving'the arms simultaneously upon the head into wheel gripping position, means'for rotating the headto rotatethe wheel under brake resistance, and means upon the head for indicating the. rotative force applied to the wheel by the head. i

- 11. A brake tester for testing the action of a brake upon a wheel of an automobile, com

: indicating the rotative f prising in combination, a head for rotating an automobile wheel under brake resistance,

consisting of. a hub ortion and a wheel enaging portion rotatlvely mounted upon the iub portion, an anti-friction bearing between said portions, means for rotating the hub portion, yielding means'for imparting the rotative movement of the hub portion tothe wheel engaging-portion, and means for orce imparted from the former portion to the latter.

12. A .braketes ter for testing the action of the brake bands upon the wlieels of an auto- .'mobile', bomprising in "combination, a supporting standhavingarotating shaft, a wheel engaging head removably mounted on 'said shaft and adapted to be positioned upon the shaft with either face toward the automobile wheel it rotates, means for rotating the head to .turn the wheel, and means for indicating the tu1'ningj .force applied to the wheel.

13. A brake tester for testing theaction of thebrake bands upon the wheels of an autom'obile, comprising in combination, a head engageable with a wheel of an automobile to rotatethe wheel under brake resistance,

means forsecuring the head to the wheel with either face toward thewheel, meansfor rotating the head and means for indicating the turning force applied to the wheel. '14. A brake. tester for testing the when of t'liebrake bands upon the wheels of an automobile, comprising in combination, ahead engageable with a wheel of an automobile to rotate the wheel under brake resistance, 'means forsecurmg the head tothe wheel with either face towardthe wheel, means for rotatilngv the head, and indicating means upon each face of the head formdicatmgtheturning force applied to the wheel.

15. A brake tester for testing the action of the brake bands upon the wheels of an automobile, comprising in combination, a headfor rotating a wheel of an automobile under brake'resistance, arins upon saidhead and adjustable to extend outwardly from'either face of the head into engagement with an automobile wheel, means for rotating the head to turn the automobile wheel, and means for .indicating'the turning force applied to thevwheel. 16., .A brake tester for testing the brake bands'upon the wheels of an automobile, comprising in combination, ahead .for rotating a wheel of an automobile under the action of I v brake resistance consisting of relatively Iro 'tating parts connected by yielding means,

means; for rotating one of. saidgparts, arms a v upon said other 'part -and adjustable to extend from one face ofthe headto rotate a wheel upon one side of the automobile and adjustable to extend from tlie opposite face i of the head to rotate a wheel upon the other side of the automobile,'an'd means for indi- I eating the turning Iorce a a brake upon a wheel of an automobile, come prising in combination, ahead engageable with-a wheel of an automobile to rotate'ithe wheel under-brake reslstanee, means for tating the head, and means for indicating mg force applied tothe wheel.

upon the opposite faces of the-head the turn-. l

18. A brake tester for testing the action of a brake upon'a wheel of an} automobile, com

prising-in combination, ahead engageable a brake upon a wheel oftan automobile, coma 10s '19. A brake tester for testingthe action of 1 prising in combination, a head for rotating a wheel ofran automobile under brake resistance and consisting of relatively movable parts provided with yielding means for imparting rotativc moyementfrom one part to the other, means for driving one of said.

parts, means upon the other part enga cable with an automobile wheel, and means or indicating the-relative movement of said parts duringthe rotation of the automobile wheel In testimony whereof, I have signedmy 1 name to this cificatlon.

S o nnEs F. COWDREY.

ins

lied to'a wheel.

'17. A brake tester for testing the action of 

